Unveiling the Milky Way: A New Low-Frequency Radio Colour Image

Strategic Insights -

A team of astronomers from the International Centre of Radio Astronomy Research (ICRAR) has created the largest low-frequency radio colour image of the Milky Way, providing unprecedented insights into the birth, evolution, and death of stars in our galaxy. The spectacular image captures the Southern Hemisphere view of our Milky Way galaxy, revealing it across a wide range of radio wavelengths, or 'colours' of radio light. Silvia Mantovanini, a PhD student at Curtin University, dedicated 18 months and approximately 1M CPU hours to construct the image using supercomputers at the Pawsey Supercomputing Research Centre.

Key Takeaways:

  • The new image offers twice the resolution, ten times the sensitivity, and covers twice the area compared to the previous GLEAM image released in 2019.
  • The image was constructed using the Murchison Widefield Array (MWA) telescope located at Inyarrimanha Ilgari Bundara, the CSIRO Murchison Radio-Astronomy Observatory.
  • The surveys involved hundreds of hours of data collection over 28 nights in 2013 and 2014, and 113 nights from 2018 to 2020.
  • The new image allows astronomers to distinguish between the gas surrounding new stars and that left behind by dead ones, revealing clearer patterns in the cosmic landscape.
  • The image may also help unravel the mysteries surrounding pulsars in our Galaxy.
  • The ICRAR researchers catalogued an impressive 98,000 radio sources across the Galactic Plane visible from the southern hemisphere.
  • Associate Professor Natasha Hurley-Walker from ICRAR, the principal investigator of the GLEAM-X survey, stated that this low-frequency image allows us to unveil large astrophysical structures in our Galaxy that are difficult to image at higher frequencies.
  • Only the world's largest radio telescope, the SKA Observatory's SKA-Low telescope, set to be completed in the next decade on Wajarri Yamaji Country in Western Australia, will have the capacity to surpass this image in terms of sensitivity and resolution.

Statistics:

  • 1M CPU hours were used to construct the image.
  • 2 surveys were conducted using the MWA radio telescope: GaLactic and Extragalactic All-sky MWA (GLEAM) and GLEAM-X (GLEAM eXtended surveys).
  • 28 nights in 2013 and 2014, and 113 nights from 2018 to 2020 were used for data collection.
  • The new image covers an area twice the size of the previous GLEAM image.
  • The image has ten times the sensitivity of the previous GLEAM image.
  • The image offers twice the resolution of the previous GLEAM image.
  • 98,000 radio sources were catalogued across the Galactic Plane visible from the southern hemisphere.

Sources:

  • International Centre for Radio Astronomy Research (ICRAR)
  • Silvia Mantovanini, PhD student at Curtin University
  • Associate Professor Natasha Hurley-Walker, ICRAR
  • Pawsey Supercomputing Research Centre
  • CSIRO Murchison Radio-Astronomy Observatory
  • Murchison Widefield Array (MWA) telescope
  • GLEAM and GLEAM-X surveys
  • SKA Observatory's SKA-Low telescope
  • Wajarri Yamaji Country in Western Australia